# Obvious belief elicitation

Working paper

Issue number:

RM/19/001

Series:

GSBE Research Publications

Publisher:

Maastricht University

Year:

2019

An investigator is interested in arbitrarily approximating a subject’s latent beliefs in obviously
dominant strategies (Li, 2017). We prove that Karni’s ascending mechanism (Karni, 2009)
does not have an obviously dominant strategy. Thus, we introduce the novel descending Karni
mechanism which always has obviously dominant strategies. Furthermore, under the assumption
that the subject chooses an obviously dominant strategy, the true beliefs can be approximated
with arbitrary precision with our mechanism. All our results hold for a very broad class of
likelihood relations, going well beyond those that are represented by probabilistic beliefs.